@book{35648,
	author = {Hoffman, Frederick L.},
	title = {The problem of dust phthisis in the granite-stone industry,},
	publisher = {Govt. print. off.,},
	year = {1922.},
	series = {Bulletin of the United States Bureau of labor statistics ;},
	address = {Washington,},
	note = {At head of title:  U.S. Department of labor, James J. Davis, secretary. Bureau of labor statistics, Ethelbert Stewart, commissioner.}
}